Adjustable stepped-opening diaphragm gas valve

ABSTRACT

A fluid pressure-operated gas valve device has an adjustably biased pressure regulator which controls the operating pressure and is initially biased so as to effect a first predetermined valve opening step when operating pressure is applied and a delayed action pressure-operated actuator which acts, following a brief delay, to increase the regulator bias and effect a second predetermined valve opening step. Means are included to adjustably preset two combinations of the initial and increased regulator bias, with means to conveniently shift the biasing from one preset combination to the other to adapt to one or the other of two fuel gases.

United States Patent 1191 Visos et a1. Apr. 2, 1974 ADJUSTABLESTEPPED-OPENING 3,451,421 6/1969 Vicenzi et a1 137 495 DIAPHRAGM GASVALVE 3,721,263 3/1973 Visos et al. 137/495 3,749,120 7/1973 Love et al137/495 X [75] Inventors: Charles D. Visos, Manchester; John J. Love;Carl A. Smith, both of St. Primary Examiner Alan Cohan Lows an ofAssistant ExaminerRobert J. Miller [73] Assignee: Emerson Electric Co.,St. Louis, Mo Attorney Agent Firm*chafles Markham [22] Filed: May 4,1973 [57] ABSTRACT 1 1 p N95 3575120 A fluid pressure-operated gas valvedevice has an adjustably biased pressure regulator which controls the 52US. Cl. 137/489.5, 137/495 Operating W and is initially biased so aseffect 51 1m. (:1. F1611 31/12 a first predetermined valve penin stepwhen operat- [58] Field of Search. 137/494, 495, 505.14, 505.15, ingPressure is pp and a delayed action Pressure- 137/489 50537, 505.4,4895; 251/61, 48; operated actuator which acts, following a brief delay,

236/7, 80, 92 A to increase the regulator bias and effect a secondpredetermined valve opening step. Means are included to 5 ReferencesCited adjustably preset two combinations of the initial and UNTED STATESPATENTS increased regulator bias, with means to conveniently 3 307 7853,1967 C 137/489 X shift the biasing from one preset combination to theurr1e 3,351,085 11/1967 Allingham 137/495 other to adapt to one or theother of two fuel gases. 3,354,901 1 1/1967 Dietiker et al 137/495Claims, 9 Drawing Figures 8 I! Y I47 34 g/[III] S1 I04 I 37 /46 1| {6/4/ 106 i i, w 1 512- A36 495 9 5 7 n "Q 1111111111n l/MA y n 1111 4klrlhllm @4 7 5 26 1 45 3 I l s I in r j e z ADJUSTABLE STEPPED-OPENINGDIAPHRAGM GAS VALVE This invention relates generally to stepped openingpressure-operated gas valves wherein application of an initial operatingpressure value effects a first valve opening step and a subsequentincrease in this pressure after a short delay effects a second valveopening step. More particularly, the invention relates to adjustmentmeans whereby the initial and subsequently increased operating pressurevalues of a stepped opening pressure-operated gas valve may be variedindependently and jointly.

It is desirable to provide adjustment means in a stepped openingpressure-operated gas valve so that the rates of fuel flow to the burnerpermitted by the first and second opening steps of the valve may beindependently varied, thereby to render the device universally adaptablefor use with a variety of burners and combustion chamber designs. It isalso desirable to provide means whereby one preset combination ofadjustments providing the desired initial and total flow rates to aparticular burner and combustion chamber when burning one kind of fuelgas may be conveniently shifted to another preset combination ofadjustments providing the desired flow rates when burning another kindof fuel gas.

Currently, the two most widely consumed fuel gases in the United Statesare the so-called natural gas and bottled or liquid petroleum gas (LPG).Because the heat value of LP gas is two to three times greater than thatof natural gas, a smaller metering orifice at the burner is requiredwhen burning LP gas than when burning natural gas if the same b.t.u.input to the burner is to be maintained. Also, because LP gas is two tothree times heavier than natural gas, it is essential when burning LPgas to maintain a considerably higher flow velocity through the burnerorifice than when burning natural gas so as to attain the requiredinjection of combustion air. To attain this higher velocity, a highersupply pressure and a higher pressure at the outlet of the controllinggas valve are required.

it is an object, therefore, of this invention to provide means in astepped opening, fluid pressure-operated gas valve for independentlyadjusting the operating pressure values which effect the first andsecond valve opening steps, for adjustably presetting two combinationsof these operating pressure values, and for conveniently shifting fromone such preset combination of pressure values to the other.

Further objects and advantages will appear from the followingdescription and accompanying drawings.

In the drawings:

FIG. 1 is a cross-sectional view of a manifold gas valve device havingan adjustable, stepped opening, pressure operated main valve constructedin accordance with the present invention;

FIGS. 2 and 3 are fragmentary cross-sectional views showing first andsecond biased positions of the pressure regulator when operating withone preset combination of biasing adjustments;

FIGS. 4 and 5 are similar fragmentary cross-sectional views showingfirst and second biased positions of the pressure regulator whenoperating with another preset combination of biasing adjustments;

FIGS. 6 and 7 are fragmentary top plan and elevational views,respectively, of the bias shifting member and latching means therefor,with the shifting member shown in an upper released position;

FIGS. 8 and 9 are detailed fragmentary top plan and elevational views,respectively, showing the bias shifting member in a downward latchedposition.

Referring to the drawings in more detail, the device comprises a bodymember generally indicated at 10. The body 10 may consist of severalsections joined together in any suitable manner so as to permit castingand boring of cavities and passages therein. In the drawing, the body isillustrated as an integrally formed structure with all passages andcavities lying in the plane of the cross-section, thereby to simplifythe description of the arrangement and cooperation of various parts andelements.

The body 10 has an inlet 12 adapted to receive a gas supply conduit andan outlet 14 adapted to receive a conduit leading to a main burner (notshown). The inlet 12 and outlet 14 are connected by a passageway 16, achamber 18, a passageway 20, a hollow rotary plug valve 22 having a mainport 44, a passageway 24, a chamber 26, and a passageway 28. A safetycutoff valve 30 cooperates with a seat 32 to control the flow from inlet12 to outlet 14. The valve 30 is manually opened by depressing a knob 34having a pin 36 and is biased to a closed position by a spring 31. Valve30 is held open by an electromagnet 38 energized through leads 41 by athermocouple junction 40 when heated by an adjacent pilot burner 42.This arrangement prevents the flow of fuel to the main and pilot burnerswhen the pilot burner is not burning.

The main port 44 in the wall of hollow rotary plug valve 22 registerswith passageway 24 when the plug valve is rotated to an on position. Theknob 34 is axially slidable relative to plug valve 22 on circularlyspaced, axially extending tangs 35 which enter circularly spaced sockets37 in knob 34. Knob 34 is thereby also keyed to plug valve 22 forrotation therewith. The plug valve 22 is further provided with acircumferentially extending pilot burner port 46 in the wall thereofwhich registers with a passageway 48 when the plug valve 22 is in an onposition. The pilot outlet 50 is connected to pilot burner 42 by aconduit 51.

A main valve 52 cooperating with an annular seat 54 formed in chamber 26around the exit of passageway 28 also controls the flow from inlet 12 tooutlet 14. Valve 52 has a stem 56 extending downward into an upperdiaphragm chamber 58 which is formed as a recess in body 10, and aspring 59 biases valve 52 downward in a closed position on its seat 54.A lower diaphragm chamber 60 is formed by a cup-shaped member 62attached to the body 10, and a flexible diaphragm 64 clamped at itsperiphery between body 10 and member 62 defines the upper and lower maindiaphragm chambers 58 and 60, respectively. The diaphragm 64 includes arelatively rigid disc member 65 centrally positioned and attachedthereto. The disc member 65 provides weight to bias the diaphragmdownward in the position shown.

The upper diaphragm chamber 58 is adequately vented to outlet passage 28through a vent 66 so that the upper side of diaphragm 64 is constantlyexposed to pressure existing in outlet passage 28. The lower diaphragmchamber 60 is also in constant communication with outlet passage 28through a passage 68, a passage 70, a passage 71, a restricting orifice72, the diaphragm chamber 78 of a pressure regulator generally indicatedat 75, and a passage 74 leading to passage 28. A valve seat 80controlled by a pressure regulating valve 82 provides additional ventingor bleed off to outlet 14 under conditions to be described. Theregulator valve 82 is formed as an integral central part of a pressureregulator diaphragm 83 which is exposed to atmospheric pressure on itsupper side through a vent 85. A spring 84 biased between the lower endof a sliding plunger member 86 and the regulator valve 82 biases valve82 on its seat 80.

The pressure regulator 75 further comprises a generally cylindricalmember 88 fitted into a cavity 90 in main body member 10, the peripheryof the regulator diaphragm 83 being clamped between member 88 and thebody member 10. The member 88 has a screwthreaded axial bore 92 whichreceives an externally screw-threaded bushing 94, and the bushing 94, inturn, slidably receives the plunger member 86. The lower end of plunger86 has a flange which limits its upward movement, and the bushing 94 isprovided with a screwdriver slot whereby the bushing may be adjustedupward or downward to vary the closing bias applied to regulator valve82 by spring 84.

A casing 96 mounted on main body pivotally supports one end of a lever98 on a pivot 100 mounted in the side wall thereof. The free end oflever 98 lies adjacent the lower end of an internally screw-threadedbushing 102 slidably mounted in an upwardly extending hollow bossportion 104 of casing 96. The slidably mounted bushing 102 threadedlyreceives an internally and externally threaded bushing 106. Bushing 106has a flange 107 at the lower end thereof which under certain conditionsengages the free end of lever 98. Bushing 106 further threadedlyreceives a screw-threaded pin 108 having a flange 109 at the lower endthereof which is also engaged under certain conditions by the free endof lever 98. A spring 110 biased between the lower end of pin 108 andthe body member 10 biases the bushing 102 upward.

Referring to FIG. 7, a pin 111 fixed in bushing 102 moves in an L-shapedslot 112 to latch bushing 102 in a depressed position. A washer 114retained in the upper end of boss 104 is engaged by pin 1 1 1 to limitthe upward movement of slidable bushing 102. The upper end of bushing102 is provided with a screwdriver slot to facilitate the rotationthereof into and out of a depressed latched position.

From the foregoing, it will be seen that the flange 107 on bushing 106and the flange 109 on pin 108 are moved simultaneously between lower andupper positions as the slidable bushing 102 is moved from an upper limitposition, shown in FIGS. 1, 2, and 3, to a lower latch position, shownin FIGS. 4 and 5. It will also be apparent that the positions of flanges107 and 109 may be independently adjusted with relation to bushing 102.The upper ends of bushing 106 and pin 108 are provided with screwdriverslots to facilitate adjustably positioning these flanges.

The casing 96 has a circular opening in the top wall thereof enclosed bya cup-shaped cover member 116. A flexible diaphragm 118 clamped at itsperiphery between the rim of cover member 116 and the casing 96 definesan upper expansible chamber 120. The diaphragm 118 is fitted with acentral rigid contact member 122 which under certain conditions engagesthe lever 98 at a point intermediate its pivoted and free ends. When theexpansible chamber 120 is in a contracted condition, the member 122 isspaced from the lever 98. A screw-threaded contact member 124 threadedlyengaged in the plunger 86 and underlying lever 98 provides means foradjusting this spacing. A screw 126 threadedly engaged in main bodymember 10 extends upward into casing 96 and is adapted to be engagedunder certain conditions by the free end of lever 98.

Communication between lower main diaphragm chamber 60 and inlet 12 isprovided through passage 68, a valve seat 128 at the upper end ofpassage 68, a valve chamber 130, a restricting orifice 132 and a passage134 to passage 24 and, thence, through hollow plug valve 22, passage 20,chamber 18, and passage 16 to inlet 12. A solenoid operated valve 136biased closed by a spring 138 cooperates with valve seat 128 to controlthis communication. The valve 136 has a stem 138 connected to theplunger of a solenoid 140. The solenoid has a winding 141 connectedacross power source terminals 142 through a space thermostat 144. Therestricting orifice 132 is larger in diameter than restricting orifice72 in bleed-off passage 71, so that when solenoid operated valve 136 isopened, the pressure will increase in diaphragm chamber 60.

The upper expansible chamber communicates with the lower main diaphragmchamber 60 through passages 68 and 70, a passage 146, a passage 148, anda restricting orifice 150, so that a pressure change in chamber 60 isslowly communicated to expansible chamber 120.

OPERATION The manifold valve device is shown in FIG. 1 in an onposition; that is to say, the hollow plug valve 22 is in an on positionin which gas may flow through its main port 44 to passage 24 and throughpilot port 46 to pilot burner 42. Also, the pilot burner is burning andcutoff valve 30 is being held open by electromagnet 38. The spacethermostat 144 is, however, in open position so that the solenoidoperated control valve 136 is biased closed, whereby communicationbetween inlet 12 and the lower diaphragm chamber 60 is cut off. Sinceupper main diaphragm chamber 58 is constantly vented to outlet passage28 through vent 66 and lower diaphragm chamber 60 is also constantlyvented to the same pressure zone through orifice 72, the diaphragm 64 isin its lower position and main valve 52 is biased closed by spring 59.

Under these conditions, when space thermostat 144 closes due to a dropin temperature, solenoid winding 141 is energized and control valve 136will open, thereby placing lower diaphragm chamber 60 in communicationwith inlet 12. Since the venting orifice 72 in passage 71 is smallerthan the inlet orifice 132 in passage 134, the pressure in lower maindiaphragm chamber 60 will now increase, causing diaphragm 64 to flexupward and move main valve 52 openward a predetermined amount againstbiasing spring 59. The extent of this initial partial opening movementof main valve 52 will be determined by the rate of pressure bleed offpermitted by the pressure regulator valve 82 which, in turn, will bedetermined by the force of the closing bias of regulator spring 84. 4

Following the opening of valve 136, the operating pressure in the maindiaphragm chamber 60 is slowly applied to the upper expansible chamber120 through passages 68, 70, 146, 148, and the restricting orifice 150.As the pressure in expansible chamber 120 slowly increases, thediaphragm l 18 flexes downward until its central contact member 122engages the lever 98. After the contact member 122 engages lever 98, thefurther downward flexing of diaphragm 118 moves the free end of lever 98and plunger 86 downward, thereby increasing the force of the closingbias on regulator valve 82 and reducing the rate of pressure bleed off.

This reduction in pressure bleed-off rate results in an increasedoperating pressure in diaphragm chamber 60, thereby causing the valve 52to be moved further openward in a second opening step. The amount ofmain valve opening movement occurring in the second step, which is alsothe total valve opening movement at the instant inlet pressure, will bedetermined by the rate of pressure bleed off permitted by the pressureregulator, which, in turn, will be determined by the nowincreasedbiasing force of regulator spring 84.

Two combinations of initial and increased regulator spring biasingforces may be preset, as indicated in FIGS. 2 and 3 and FIGS. 4 and 5,respectively.

In a first combination, the initial biasing force is adjustably presetby rotation of screw-threaded bushing 94 and the increased biasing forceby rotation of screwthreaded pin 108. Referring to FIG. 2, it will beseen that rotation of screw-threaded bushing 94 adjusts the initial biasof regulator spring 84 when the expansible chamber 120 is contracted.Referring to FIG. 3, it will be seen that rotation of pin 108 varies theposition of its flange 109 and variably limits the downward swing oflever 98 and, therefore, limits the increase in biasing force of spring84 effected by expansion of chamber 120.

In a second combination, the initial biasing force is preset by rotationof screw-threaded bushing 106, and the increased force is adjustablypreset by rotating the adjustment screw 126. Referring to FIG. 4, itwill be seen that rotation of bushing 106 variably limits the upwardtravel of lever 98, and referring to FIG. 5, it will be seen thatrotation of screw 126 variably limits the downward travel of the freeend of lever 98. It will also be noted that both the initial andincreased biasing forces are greater in the second preset combinationshown in FIGS. 4 and 5.

The initial and increased biasing of the pressure regulator spring, aseffected by one or the other of these two preset combinations, may beconveniently selected by positioning the slidably mounted bushing 102 inits upper released position shown in FIGS. 2, 3, 6, and 7, or in itslower latched position shown in FIGS. 4, 5, 8, and 9. When slidablebushing 102 is in its upper released position of FIGS. 2 and 3, thelever 98 does not engage the underside of flange 107. The upwardmovement of plunger 86 is limited, under these conditions, by engagementof the flange on the lower end thereof with adjustable bushing 94, whichdetermines the initial bias in this case. When slidable bushing 102 isin its depressed and latched position of FIGS. 4 and 5, the downwardmovement of lever 98 is not limited by the flange 109 on threadedlyadjustable pin 108. The downward movement of lever 98 is limited byadjusting screw 126 in this case.

From the foregoing, it will be seen that the initial and total flow ofgas to a burner may be independently adjusted by means of screw 124,which adjusts the space between lever 98 and contact member 122. It willalso be seen that two combinations of initial and total flow may bepreadjusted or preset and that an operator can quickly and convenientlyshift from one of these preset combinations to the other by the meredepression of slidable bushing 102 and the slight rotation thereof to alatched position, or from the other to the one by a slight rotation ofbushing 102 to release it.

These two preset combinations of adjustments may be made when thedevices are manufactured to meet the requirements of a gas burningappliance manufacturer to whom they are supplied. In the field, the gasburning appliance is, therefore, quickly and conveniently adaptable toburn either natural or liquid petroleum gas.

We claim:

1. In a stepped-opening pressure-operated valve device, a biased closedmain valve, an expansible chamber operative when expanding to move saidvalve openward, means to supply fluid pressure to said chamber includingan open or closed control valve, an adjustably biased pressure regulatorcontrolling the pressure in said chamber and operative to effect anincrease in pressure when the bias thereon is increased, a delayedaction actuator operative to increase the regulator bias subsequent toopening of said control valve, first adjustable means for presetting aninitial regulator bias and for presetting a limit to which said actuatorincreases said initial bias, second adjustable means for presetting ahigher initial regulator bias and for presetting a higher limit to whichsaid actuator increases said higher initial bias, and a member movableoppositely to alternately shift said first and second adjustable meansbetween operative and inoperative positions.

2. The device claimed in claim 1 in which said first adjustable meanscomprises independently adjustable elements for presetting an initialregulator bias and for presetting the limit to which said actuator canincrease the initial regulator bias.

3. The device claimed in claim 1 in which said first and secondadjustable means each comprise independently adjustable elements forpresetting an initial regulator bias value and for presetting the limitto which said actuator can increase the initial bias value.

4. The device claimed in claim 3 in which said first and secondadjustable means each comprise two independently adjustable abutmentsand in which means movable with said actuator engages said adjustableabutments of one or the other of said adjustable means.

5. The device claimed in claim 4 in which one of said abutments of saidfirst adjustable means and one of said abutments of said secondadjustable means are adjustably mounted on said movable member and arejointly shifted between a first operative position in which one of saidabutments is engaged by said means movable with said actuator and theother is not and a second operative position in which the other of saidabutments is engaged and the one is not.

6. In a stepped-opening diaphragm valve device having a biased closedmain valve, means controlling the operating pressure applied to one sideof the diaphragm including a control valve and a spring biased pressureregulator operative in response to an increase in the bias thereon toeffect increased opening of said valve, and a delayed action actuatoroperative to increase the regulator bias from an initial preset bias toa greater bias in a short period of time following the opening of saidcontrol valve; an improvement comprising means movable with and formingan operative connection between said actuator and said regulator biasingspring, two pairs of spaced abutments arranged to be selectively engagedby said operative connecting means, the first abutment of each pairestablishing an initial regulator bias and the second abutment of eachpair establishing a limit to which said actuator increases said bias,and means to jointly shift said first abutment of one pair and saidsecond abutment of the other pair relative to the first abutment of theother pair and the second abutment of the first pair, whereby either oftwo combinations of initial and increased regulator bias values may beconveniently selected.

7. The device claimed in claim 6 in which said first abutment of onepair of abutments and said second abutment of the other pair ofabutments are mounted on a member movable with respect to the other ofsaid abutments, said movable member being movable to a first operativeposition in which said first abutment of said one pair is operativelyengaged and said second abutment of said other pair is spaced fromengagement, and said movable member being movable oppositely to a secondoperating position in which said second abutment of said one pair isoperatively engaged and said first member is spaced from engagement.

8. The device claimed in claim 7 including spring means biasing saidmovable member in one of said operative positions and means releasablylatching said movable member in the other of said operative positions.

9. The device claimed in claim 7 in which two of said abutments areadjustably mounted on said movable member.

10. The device claimed in claim 7 in which one abutment of each pair isadjustably mounted on said movable member and one abutment of each pairis adjustably mounted on support means fixed with relation to saidconnecting means and said movable member.

1. In a stepped-opening pressure-operated valve device, a biased closedmain valve, an expansible chamber operative when expanding to move saidvalve openward, means to supply fluid pressure to said chamber includingan open or closed control valve, an adjustably biased pressure regulatorcontrolling the pressure in said chamber and operative to effect anincrease in pressure when the bias thereon is increased, a delayedaction actuator operative to increase the regulator bias subsequent toopening of said control valve, first adjustable means for presetting aninitial regulator bias and for presetting a limit to which said actuatorincreases said initial bias, second adjustable means for presetting ahigher initial regulator bias and for presetting a higher limit to whichsaid actuator increases said higher initial bias, and a member movableoppositely to alternately shift said first and second adjustable meansbetween operative and inoperative positions.
 2. The device claimed inclaim 1 in which said first adjustable means comprises independentlyadjustable elements for presetting an initial regulator bias and forpresetting the limit to which said actuator can increase the initialregulator bias.
 3. The device claimed in claim 1 in which said first andsecond adjustable means each comprise independently adjustable elementsfor presetting an initial regulator bias value and for presetting thelimit to which said actuator can increase the initial bias value.
 4. Thedevice claimed in claim 3 in which said first and second adjustablemeans each comprise two independently adjustable abutments and in whichmeans movable with said actuator engages said adjustable abutments ofone or the other of said adjustable means.
 5. The device claimed inclaim 4 in which one of said abutments of said first adjustable meansand one of said abutments of said second adjustable means are adjustablymounted on said movable member and are jointly shifted between a firstoperative position in which one of said abutments is engaged by saidmeans movable with said actuator and the other is not and a secondoperative position in which the other of said abutments is engaged andthe one is not.
 6. In a stepped-opening diaphragm valve device having abiased closed main valve, means controlling the operating pressureapplied to one side of the diaphragm including a control valve and aspring biased pressure regulator operative in response to an increase inthe bias thereon to effect increased opening of said valve, and adelayed action actuator operative to increase the regulator bias from aninitial preset bias to a greater bias in a short period of timefollowing the opening of said control valve; an improvement comprisingmeans movable with and forming an operative connection between saidactuator and said regulator biasing spring, two pairs of spacedabutments arranged to be selectively engaged by said operativeconnecting means, the first abutment of each pair establishing aninitial regulator bias and the second abutment of each pair establishinga limit to which said actuator increases said bias, and means to jointlyshift said first abutment of one pair and said second abutment of theother pair relative to the first abutment of the other pair and thesecond abutment of the first pair, whereby either of two combinations ofinitial and increased regulator bias values may be convenientlyselected.
 7. The device claimed in claim 6 in which said first abutmentof one pair of abutments and said second abutment of the other pair ofabutments are mounted on a member movable with respect to the other ofsaid abutments, said movable member being movable to a first operativeposition in which said first abutment of said one pair is operativelyengaged and said second abutment of said other pair is spaced fromengagement, and said movable member being movable oppositely to a secondoperating position in which said second abutment of said one pair isoperatively engaged and said first member is spaced from engagement. 8.The device claimed in claim 7 including spring means biasing saidmovable member in one of said operative positions and means releasablylatching said movable member in the other of said operative positions.9. The device claimed in claim 7 in which two of said abutments areadjustably mounted on said movable member.
 10. The device claimed inclaim 7 in which one abutment of each pair is adjustably mounted on saidmovable member and one abutment of each pair is adjustably mounted onsupport means fixed with relation to said connecting means and saidmovable member.